JPS58120895A - Size agent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a sizing agent with excellent sizing effects.

More specifically, the present invention relates to a sizing agent that can significantly improve the dry and wet strength and sizing of paper.

The present inventors completed the present invention as a result of intensive research aimed at producing a sizing agent that is inexpensive and can improve both the strength and sizing of paper.

That is, the present invention provides the following general formulas (A), (B)
, (0) and Φ) as a structural unit.

(In the formula, R1 is OH1 or 02HB: R2* R4
* “7 is H or OH3: Ra is H or 000M:
Rs, R, is OH, or 02H5; M is H, alkali metal or ammonium salt;
Each Y hails an anion. ) Those represented by general formula (A) include vinyl acetate,
Vinyl esters such as vinyl propionate can be used, but vinyl acetate is preferred from an economic standpoint. The copolymerization ratio of the structural units is preferably 10 to 85 moles. If it is less than 10 molar, the stability of the emulsion is poor and popcorn polymerization is likely to occur. If the molar ratio exceeds 85, the size effect will be insufficient.

Styrene and metastyrene can be used as the compound represented by the general formula (B), but styrene is preferred from an economic standpoint. The copolymerization ratio of the structural units is preferably 10 to 85 molar.

If it is less than 10 moles, the size effect becomes opaque, and if it is more than 85 moles, popcorn polymerization tends to occur.

Examples of compounds represented by general formula (0) include acrylic acid,
Unsaturated basic acids such as methacrylic acid and unsaturated dibasic acids such as maleic acid, fumaric acid and itaconic acid can be used. The copolymerization ratio of the structural units is preferably 0.5 to 10 molar. If it is less than 0.5 molar, the stability of the emulsion will deteriorate, if it is more than 10 molar, the size effect will be insufficient, and if it is alkaline, it will be difficult to exhibit the effect.

The structural unit represented by the general formula (D) is obtained by neutralizing the aminoethyl ester of acrylic acid or the aminoethyl ester of methacrylic acid with a mineral acid such as nitric acid, hydrochloric acid or phosphoric acid, and converting it into epichlorohydrin, epibromohydrin or ebiodohydrin. It is a cationic monomer obtained by adding shrimp iodohydrin such as phosphorus. Examples of aminoethyl esters of acrylic acid or methacrylic acid include 2-dimethylaminoethyl acrylate, 2-diethylaminoethyl acrylate, and amineethyl esters of methacrylic acid corresponding to these esters. Co-FX of the structural unit
The unit ratio is preferably 0.5 to 10 molar ratios.

The co-association reaction of monomers is carried out using methyl alcohol, isoflobil alcohol, acetone, etc., water, or a mixed solution of these as a solvent, using persulfate, persulfate-sulfite, and peroxide. It can be carried out by a conventional method at 10 to 100 C using a polymerization catalyst such as hydrogen, 2,21-azobis(2-amidinopropane) dihydrochloric acid group, or azopispronitrile.

In order to obtain a stable emulsion sizing agent with good water dispersibility, it is desirable to use water alone, water-methyl alcohol, water-isoflobil alcohol, or water-77ton system as the solvent.

In producing the sizing agent of the present invention, it is possible to copolymerize the monomers in advance using a suitable emulsifier, but even without using an emulsifier, a copolymer emulsion can be obtained by self-emulsification during the copolymerization reaction process. Therefore, the adverse effects of emulsifiers in practical applications are well known, and from an economic standpoint, it is advantageous not to use emulsifiers.

As the protective colloid, it is also possible to use megvinyl alcohols, water-bathable cell derivatives such as carboquine methyl cellulose, starch derivatives, and the like.

The sizing agent of the present invention can be applied to the surface of paper using a size press machine, tab size machine, roll coater, etc. (hereinafter referred to as surface size), or internally added to a beater, etc. Although it is possible, applying it to the surface size is more effective in improving the strength and sizing of the paper.

Next, manufacturing examples and test examples of the sizing agent of the present invention will be explained. In the examples, all values are t% by weight.

Production example 1 480 g of 2-dimethylamine ethyl methacrylate and 2 g of water
After neutralizing the 00v mixed m solution with 6N nitric acid, 280f of epichlorohydrin was added to the solution, and the mixture was reacted at 50C for 10 hours to form a monomer (hereinafter referred to as D) having the following structural formula ['l].
It is called Kf'-1. ) and diluted with water to make a 25% solution.

Next, in a fourth flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen blowing tube, add vinyl acetate 17.2F, acrylic@2.91.25% DEIP-I75f, and styrene 176.8? , water 7001 was added and mixed.

After removing oxygen in the reaction system using nitrogen and raising the temperature to 6 oc, 2,21-azobis(2-amidinopropane) dihydrochloride α322 as a polymerization catalyst was dissolved in water 301F and added. Furthermore, 80
The reaction was carried out for 2 hours at c.

The concentration of the reaction product was adjusted with water to give a solid content of 20%. It was a milky white emulsion.

Production Example 2 In the same apparatus as Production Example 1, 51.7 f of vinyl acetate, 2.9 f of acrylic acid, 25% D-concave P-175r, and 15 styrene were added.
5.2f and 700f of water were added and mixed. After removing the residue in the reaction system using nitrogen and raising the temperature to 60C, 1f of 2,2'-azobis(2-amidinopropane) dihydrochloride was dissolved in 50 tons of water and added as a polymerization catalyst. Further, the reaction was carried out at 60° C. for 7 hours while flowing nitrogen.

The reaction product was adjusted to 11K degrees with water to give a solid content of 20%. It was a milky white emulsion.

Production Example 3 Vinyl acetate A6? was added to the same equipment as Production Example 1. , acrylic acid 0,32.25% DJIIP-)Z! M, styrene;
After raising the temperature to 70C, add 0.0% potassium persulfate as a polymerization catalyst.
2? Water 10? IQIF was added to the solution. Further, the reaction was carried out at 70C for 5 hours while flowing nitrogen.

The concentration of the reaction product was adjusted with water to give a solid content of 20 grams. It was a milky white emulsion.

i+! ! ! Production Example 4 In Production Example 1, nitric acid was used to neutralize 2-dimethylamine ethyl methacrylate, but instead of nitric acid, 6N salt St was used for neutralization, and the rest was exactly the same as Production Example 1. The reaction was carried out to form a monomer (
Hereinafter, it will be referred to as DFIP-71. ) was obtained.

In a device similar to Production Example 1, vinyl acetate 1Z21, acrylic acid 1.4f, 25% D concave p-14α72, and styrene 7B were added.
? , 320f of water was added and mixed. After removing oxygen in the reaction system using nitrogen and raising the temperature to 50p, 0.5f of potassium persulfate was added to 20% of water. 0.52 of sodium bisulfite was dissolved in 20 tons of water and added thereto. 50 minutes while flowing nitrogen further.
The reaction was carried out at 80C for 5 hours and at 80C for 2 hours.

The concentration of the reaction product was adjusted with water to give a solid content of 20%. It was a milky white emulsion.

Production Example 5 In the same apparatus as Production Example 1, vinyl acetate 50.1F, maleic acid 5.8V, 25%i) gP-1125,1? ,
Then, 41.6 r of styrene and 280 l of water were added and mixed. After removing oxygen in the reaction system using nitrogen, the temperature was raised to 60°C, and 2v of 2,21-azobis(2-amidinopropane) dihydrochloride was dissolved in water at 50rK as a polymerization catalyst and added thereto. Further, the reaction was carried out at 60C for 8 hours while flowing nitrogen.

The reaction product was concentrated with water to a solid content of 20 qg. It was a milky white emulsion.

Comparative Example 1 Acrylamide 24.9t, acrylic acid &6f, styrene 62.4t, isopropyl alcohol 18? ,Wed 230? was added to the same equipment as in Example 1 and mixed.

After removing oxygen in the reaction system using nitrogen, 2,21-azobis(2-amidinopropane) dihydrochloride α452 was dissolved in 101P water and added as a polymerization catalyst. Further, the temperature was raised from room temperature to 80C while nitrogen was being flowed, and the reaction was continued at 80C for 6 hours.

The concentration of the reaction product was adjusted with water to give a solid content of 25%. It was a milky white emulsion.

Test Example 1 The emulsions of Production Examples 1 to 5, the emulsions of Comparative Example 1, and commercially available sizing agents A and E were diluted to a solid content of 1.0 yen, and a receiving paper (Tsuboyari SST/ n?) and dried and rolled for 3 minutes in a 100C rotary drum dryer to obtain paper. The Steckigt sizing degree, dry tear length and wet tear length of this paper were determined by J-K5P8112, J-KSF 8115, rIs, respectively.
It was measured according to P 8155, and the results are shown in Table 1.

Table 1 Test Results Patent Applicant Nippon Carlit Co., Ltd. Procedures Amendment Document February 15, 1980 Haruki Shimada, Commissioner of the Japan Patent Office 1 Indication of the case 1982 Patent Application @ 1557 2 Name of the invention Supai Sizing Agent (5) Postal address for the person making the amendment: No. 100 Telephone: 03 (2131) 50214;
Column 5 of “Detailed Description of the Invention” of the specification to be amended, contents of the amendment (Revised “azobisbutyronitrile” in line 4 of page 6 of specification #I to “azobisisobutyronitrile”) do.

Claims (1)

[Claims] (1) The following general formula (c)), (B), (0)
and (D) A sizing agent whose main component is a copolymer whose structural unit is the monomer formed by (D). (In the formula, R1 is OH3 or 0)
R7 is ■ or CH3: R3 is H or 000M: R5
, R, , are CH3 or 0zH5; M is H, alkali metal or ammonium; x is C1, Br or engineering; Y is an anion, respectively. ) (2) The following formulas (A'), (B'), (C'
) and (D') as structural units. (In the formula, Y represents an anion.) (5) Characterized by a copolymer whose structural unit is a monomer represented by the following formula (A), (B, (0) and (bi). (4) The sizing agent according to claim 2 or 3, wherein Ye is NOp. (5) The sizing agent according to claim 2 or 3, wherein YO is 01°.